Did you know that humans have four different kinds of hair? And that women have just as much body hair as men? That androgens make beards grow and cause baldness? And that we still don’t fully understand the lifecycle of hair? At the 14th Day of Scientific and Technical Exchanges, put on by Cosmed, Alexandre Guichard of the Besançon university hospital’s dermatology department took his listeners on a discovery tour of the hair fibre.